Related to r11189: avoid calling factor_table::getNextSlots() if the ship doesn't have the dynamic linking flag.

Basically, hitting "o" on any ship with more than 6 slots in a bank could crash FSO, even without the flag. Reported by Spoon.

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@11192 387891d4-d844-0410-90c0-e4c51a9137d3
fix Mantis #3132 (is-iff returns true when the target is destroyed)

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@11193 387891d4-d844-0410-90c0-e4c51a9137d3